[BUG] serious `npm ci` performance regression in 7.21.0

[sarahkadar]

Is there an existing issue for this?

• I have searched the existing issues

Current Behavior

time npm ci --no-audit --prefer-offline

npm@7.20.6:

added 3593 packages in 24s

________________________________________________________
Executed in   24.62 secs    fish           external
   usr time   26.91 secs  238.00 micros   26.91 secs
   sys time   23.69 secs  871.00 micros   23.69 secs

npm@7.21.0:

added 3593 packages in 37s

________________________________________________________
Executed in   37.41 secs    fish           external
   usr time   39.74 secs  264.00 micros   39.74 secs
   sys time   24.86 secs  933.00 micros   24.86 secs

i did an rm -rf node_modules && rm -rf workspaces/test/node_modules by hand each time and the cache is completely warm.

i tested this on my laptop (2019 16" MBP, Core i9, 64 GB RAM, internal SSD) but i see this slowdown in our CI as well (GitLab CI, custom GitLab runners on AWS, c5d.xlarge instances using docker machine)

Expected Behavior

npm@7.21.0 not be 50% slower

Steps To Reproduce

1. clone https://github.com/KTamas/npm7210-perf-regression
2. run npm ci --no-audit --prefer-offline (twice so the cache is warm)

Environment

• OS: MacOS 11.5.2
• Node: 16.7.0
• npm: 7.20.6 and 7.21.0

[isaacs]

Thanks for the clear reproduction case! Was able to track this down to two very hot code paths in node-tar that were doing more work than needed. Should be much improved in the next release.

[sarahkadar]

thanks!

[sarahkadar]

@isaacs this is quite an improvement but unfortunately still not quite the same level of performance as npm@7.20.6

re-ran the tests on node@16.8.0

npm@7.20.6

________________________________________________________
Executed in   27.28 secs    fish           external
   usr time   29.39 secs  261.00 micros   29.39 secs
   sys time   25.84 secs  872.00 micros   25.84 secs

npm@7.21.1

________________________________________________________
Executed in   31.78 secs    fish           external
   usr time   33.49 secs  228.00 micros   33.49 secs
   sys time   25.63 secs  887.00 micros   25.62 secs

i ran them several times so this is not within the margin of error.

edit: node@16.7.0 results are closer

npm@7.20.6

________________________________________________________
Executed in   28.43 secs    fish           external
   usr time   29.01 secs  186.00 micros   29.01 secs
   sys time   25.27 secs  797.00 micros   25.27 secs

npm@7.21.1

________________________________________________________
Executed in   30.15 secs    fish           external
   usr time   32.64 secs    0.40 millis   32.64 secs
   sys time   24.63 secs    1.25 millis   24.63 secs

don't mean to be splitting hairs here. but maybe there might still be some room for improvement?

totally understand if this is not a priority at this point though.

[eljenso]

I have come across a similar problem with a single package: material-design-icons

Here you'll find a repo for reproduction: https://github.com/eljenso/install-perf_material-design-icons
Those are my results for running npm ci with different versions of npm under node@14.17.6:

npm@7.20.6

$ time npm ci

added 1 package, and audited 2 packages in 3m

found 0 vulnerabilities
npm ci  159.45s user 27.88s system 123% cpu 2:31.24 total

npm@7.21.0

$ time npm ci

added 1 package, and audited 2 packages in 10m

found 0 vulnerabilities
npm ci  646.46s user 34.43s system 108% cpu 10:29.35 total

npm@7.24.1

$ time npm ci

added 1 package, and audited 2 packages in 4m

found 0 vulnerabilities
npm ci  234.08s user 30.42s system 117% cpu 3:44.50 total

But the most interesting results are when using different versions of npm@6.

npm@6.14.14

$ time npm ci
npm WARN prepare removing existing node_modules/ before installation
added 1 packages in 53.523s
npm ci  54.36s user 32.50s system 161% cpu 53.809 total

npm@6.14.15

$ time npm ci
npm WARN prepare removing existing node_modules/ before installation
added 1 packages in 649.631s
npm ci  671.23s user 38.71s system 109% cpu 10:49.97 total

In other words: upgrading to the latest version of npm@6 increased the time for npm ci tenfold.
As we are using still using npm@6, it would be great if the performance under npm@6 could be improved as well.